1. Field of the Invention
The present invention relates to ion generators, in particular, ion generators that generate ions by electrical discharge between discharging needle electrodes and ground electrodes.
2. Description of the Related Art
Japanese Unexamined Patent Application Publication No. 2005-142131 discloses a static eliminator including a plurality of discharging needle electrodes disposed with a predetermined spacing therebetween in a longitudinal direction and a cover having openings toward which the discharging needle electrodes protrude. The surface resistivity of this cover is set to less than or equal to 107 Ω/mm2.
The cover prevents operators' fingertips from coming into contact with the discharging needle electrodes. However, when the surface resistivity of the cover is less than or equal to 107 Ω/mm2, generated ions are excessively absorbed by the entire cover, resulting in a reduction in static-elimination capacity.